Background: Cell cycle kinetic measures have been shown to have prognostic significance in breast cancer. The proliferative activity of tumors has been investigated with different approaches among which the use of monoclonal antibody MIB1 (against Ki-67 antigen) represents an easy and reliable means of assessing cell proliferation. The prognostic value of quantitative estrogen receptor (ER) and progesterone receptor (PR) immunohistochemical analysis has been also well established. This study was conducted in order to demonstrate our experience with an immunohistochemical detection of the markers of proliferation and hormone status in formalin-fixed paraffin-embedded samples of 1224 primary breast carcinomas.
Methods and results: In this study, the proliferative activity of breast carcinomas was investigated using immunohistochemistry with the monoclonal antibody MIB1 (Immunotech). For a detection of ER and PR content in breast carcinomas, the antibodies ER1D5 (Dakopatts) and PR10A9 (Immunotech) were used. Immunohistochemical studies were performed on sections of formalin-fixed paraffin-embedded tissues using the antigen retrieval method with a microwave oven irradiation. The MIB1 index was related to the histologic grade of ductal invasive carcinoma (p < 0.001). The study also revealed a significant correlation of the MIB1 index with ER values in grade II (p < 0.1) and grade III (p < 0.001), but not in grade I of ductal invasive carcinoma. Prognostic value of an immunohistochemical analysis of the MIB1 proliferative index, ER and PR status was determinated in this study.